Contact operation



March 26, 19466 J. T. 1... BROWN 2,397,123

CONTACT OPERATIQN Filed April 30, 1943 2 Sheets-Sheet 1 INVENTOR J. Z'L.BROWN ets-S pril TORN

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Incorporated,

New York, N. Y., a corporation of New York Application April 30, 1943,Serial No. 485,106

12 Claims.

This invention relates to relays and has for its object the control ofthe times at which a plurality of contacts will operate in response to asingle circuit operation.

There has been developed a glass-sealed reed device acting as thecontact means for a relay which may be placed axially within theenergizing coil where it becomes extremely rapid in action and verysensitive. Such device is disclosed in Patent 2,289,830 granted toEllwood July 14, 1942, and has been employed in numerous combinations,one Of which showing sequential operation of a plurality of such contactdevices is shown in Patent 2,243,399 granted to Skellett May 27, 1941.

The present invention, in one of its embodiments, contemplates thesequential operation of a plurality of contact sets in combination withmeans for releasing such contacts in either the same or the reversesequence to that used in their operation.

In another of its embodiments this invention contemplates thesimultaneous operation of a plurality of contacts even where suchcontact sets differ in their inherent operating characteristics.

Simultaneous operation may be secured in different manners. One exampleis that where the magnetic circuits of two or more contact sets areplaced in series while the electrical circuits for energizing them areplaced in parallel. This is a positive method for insuring that when onecontact operates the others also will operate. Another example is wherea number of contact sets are surrounded by one coil in which case eachcontact set is provided with an individual low reluctance returnmagnetic circuit. This is nega tive in that by this method the contactscan be made to operate together as well as when they are in separatecoils.

In accordance with a feature of this invention the change of reluctancethrough the contact set is employed to affect a neighboring contact set.Where simultaneous operation is desired the two contact sets are placedmagnetically in series so that the lowering of the reluctance in oneportion of the circuit acts as a lowering of the reluctance of thecircuit as a whole and thus speeds the operation of another contact setbeyond its inherent characteristics. In another example where sequentialoperation is desired the contact sets are placed, magnetically inparallel so that when one operates the consequent lowering of thereluctance therethrough results in stealing the field from the otherwith the result that the operation of such other is retarded beyond itsinherent characteristics.

In accordance with the present invention a plurality 0f glass-sealedcontact sets are linked together in an electrical or magnetic circuit insuch manner that their sequence of operation is rigidly controlled.

Where sequential operation is desired a plurality of contact elementsmay be operated in a circuit bearing a general resemblance to a filtercircuit with the energizing coils in series and a like plurality ofcondensers in multiple. When the circuit is closed the contacts operatein sequence as the condensers become charged. The deenergization orrelease of the contacts may be accomplished by opening the circuit ateither end whereby the contacts will release in sequence and the orderor the direction of such sequential release will depend on which end ofthe circuit is opened.

A feature of the invention is a plurality of contact sets each having anindividual energizing coil, all of said coils being connected in asingle circuit and responsive to a single circuit operation with meansprovided to control the sequence of operation of said contact sets.

Another feature of the invention is a plurality of contact sets eachhaving an individual energizing coil arranged in a network in which themagnetic circuits of the contact sets are in series and the electricalcircuits are in parallel.

Another feature is a plurality of contact sets energized by a commoncoil and each having a magnetic circuit of such low reluctance that thepercentage change therein caused by the change in reluctance of aneighboring contact set is negligible.

The drawings consist of two sheets having twelve figures, as follows:

Fig. 1 is a schematic circuit diagram partly schematic in nature showingone means for controlling the sequence of operation of a plurality ofcontacts;

Fig. 2 is a side sectional view;

Fig. 3 is an end view of an arrangement in which a plurality of sets ofcontacts are placed magnetically in series while the electricaloperating coils are placed in parallel;

Fig. 4. is a sectional view of one type of magnetic circuit switchingelement;

Fig. 5 is a view of a similar device of the same nature, in which abreak-before-make operation is achieved;

Fig. 6 is a left-hand end view;

Fig. 7 is a sectional side view;

Fig. 8 is a right-hand end view of a device in which a plurality ofcontact sets energized by a common coil are arranged in a manner tocause simultaneous operation to such contact sets;

Fig. 9 is a left-hand end view;

Fig. is a sectional side View;

Fig. 11 is a right-hand end view of a similar device in which thecontact sets are arranged to operate in sequence; and

Fig. 12 is a perspective view of a device arranged either in accordancewith Figs. 6, '7 and, 8 or in accordance with Figs. 9, 10 and 11.

The arrangement of Fig. 1 is a circuit network arranged to cause thesequential operation of a plurality of contacts. The contact sets i, 2,3 and l are controlled by the coils 5, 6, l and 8, respectively, and maybe conventional armature and contact arrangements or they may be of thesealed magnetic reed type such as those disclosed in the Ellwood patent.This circuit arrangement is energized by a batteiy 9 and controlled bytwo keys ill and it. There are also condensers l2, l3 and I l eachconnected from a joint between the junction of two of the coils such as5 and 6 to the return conductor iii. In operation, if the key l l isfirst closed and the key it is later closed the contacts to becontrolled are operated in sequence in the order l, 2, 3 and 3, due tothe well-known action of the charging of the condensers in such afilter-like network.

The deenergization of these contacts may be controlled in the order i,2, 3 and i by opening the circuit by the key ll] or in the order 6, 3, 2and l by opening the circuit by the key ll first.

The arrangement of Figs. 2 and 3 show two Ellwood units it and IT eachinserted in its own operating coil 28 and i9, respectively. The magneticcircuit of the'two sealed reed contact sets is arranged in seriesthrough the external magnetic yokes 2D and 2t and the two coils l8 andi9 are so connected in parallel that this series magnetic circuit willbe properly energized. Therefore when the circuit to which theconductors 22 and 23 is energized and the consequent energization of thecoils i8 and i9 is slowly raised the two contact sets will operatetogether. The reason [or this is that even though the two units may bedifferent in their sensitivity the movement of one results in a loweringof the reluctance of the series magnetic circuit whereupon the othercontact set will immediately follow through the increased field aifordedthereby.

There are actually two types of effect involved here. One is achievedthrough placing the magnetic reluotances in series and the other isachieved by placing the coils properly poled in parallel. The twoeffects are similar, the elfect being greatest when they are combined asshown in Fig. 2. Conversely, putting the magnetic reluctances inparallel has the same type of effect as putting the switches in separatecoils all in series, and these magnetic and electrical arrangements canbe combined in various ways.

Fig. 4 shows a sealed reed contact device having a transfer contactarrangement and which is subject to the same time control of itsoperation as the simple reed device known as the Ellwood unit. Thisdevice consists of a glass envelope 2 2i having two stationary contactssealed in its left-hand end and a moveable contact arrangement sealed inits right-hand end. The lead in wire 25 and the contact element 26 maybe non-magnetic. The lead in wire 2i and the pole-piece and contactelement 28 are of magnetic material. The

tube 29 and the pole-piece 30 are of magneticmaterial. A spring 3! holdsan armature 32 normally away from the gap between the elements 23 and3G, and into electrical contact with the part 26. Upon energization thearmature 32 bridges the gap between the elements 28 and and makeselectrical contact with the element 28. The device of Fig. 5 is animprovement on the device of Fig. 4 in that the so called stationaryelement 33 is given a certain degree of resiliency by means of a spring34 by which it is attached to the lead in wire 35, through which amake-beforebreak operation is achieved. The corresponding elements ofthis device are made of the same materials as those of Fig. 4. By thismeans a more intimate magnetic connection may be made between themagnetic parts 33, 36 and 3? and a more sure electrical connection maybe made between the elements 36 and In operation the part 33 movestoward the part 36 and makes electrical connection therewith before thepart 36 moves away from the back contact. Afterwards parts 33 and 36move together until stopped by the engagement of part at by the part 31.In both these devices it will be seen that the reluctance of the paththrough the device is lowered upon its operation so that when two ormore are placed magnetically in series the operation or the movementtoward operation will lower the reluctance of the whole circuit andspeed up the operation of the others.

In Figs. 9, 10 and 11 a relay made up of a single coil enclosing threeEllwood units is shown. Now it so happens that as in most apparatus ofthis nature it is difficult to produce on a mass basis a large number ofthese contact units having exactly the same operating characteristics ordegree of sensitivity. For practical purposes this is a matter of littleconcern and indeed it is not difficult by test and selection to pick outof a batch of completed units any given number having likecharacteristics, By the same token it is as easy to pick out othershaving slightly difierent characteristics. Where it is desired toproduce a relay having three sets of make contacts which will operatesequentially three units 38, 39 and 40 may be selected so that the unit38 will operate on the least number of ampere turns, unit 39 on anintermediate value and unit w on the greatest. If each of these wasprovided with its own energizing coil and the current in the three coilswas simultaneously (as in a series connection) slowly raised the contactunits would operate in the order 38, 39 and M3. However, the differenceis quite small and can be exaggerated by the means of Fig. 10 by placingthem all together in one coil. Now as the current in coil All is slowlyraised there will come a point where the device 38 operates. Thisresults in a lowering of the reluctance therethrough with the resultthat the unit 38 steals the field away from the others. Therefore theoperation of 39 is delayed and it in turn and in a like manner delaysthe operation of unit 45. The contact units 38, 39 and it] and the coilll may be connected to contact pins on a base 52 so that this relay maythen be covered as indicated in Fig. 12 and made to appear and to havethe convenience of the modern devices of this nature.

Figs. 6, 7 and 8 show a similar arrangement where simultaneous operationof a plurality of units is desired. While the units 33, M and may becarefully selected to have as nearly like characteristics as possiblethis is not necessary. In this case each unit is provided with anindividual return magnetic path so that the change of reluctance in onesuch magnetic circuit will have no effect on the others. A magneticstrip 45 is welded to the'magnetic lead in wire 41 of the unit 45 andbrought around the outside of the coil 48 into close proximity to themagnetic lead in element 49, the gap between the two being made onlylarge enough to provide suflicient electrical contact separation. Thisreturn strap 46 may be used, as shown, as an electrical conductor forthe purpose of mounting as shown in Fig. 12. Similar return straps areshown associated with the other units 43 and 44.

Generally, the effect desired with the arrangement of Fig. 7 may beheightened by quickly energizing the coil 48, as by providing a largercurrent therein than is actually necessary to operate the units. By thesame token the eflect desired with the arrangement of Fig. 10 may beheightened by slowly energizing the coil 4! as by the condenser andinductance network arrangement as in Fig. 1.

Other combinations of these elements and which come within the term ofapplicants claims will occur to those skilled in the art and areintended to be covered by the instances disclosed herein by way ofexample.

What is claimed is:

l. A relay arrangement comprising a plurality of separate contact setseach having a separate energizing coil, all said coils being included ina single circuit including means to control the sequence of operation ofsaid contact sets.

2. A relay arrangement comprising a plurality of separate contact setseach having a separate energizing coil, all said coils being included ina single circuit and responsive to a single circuit operation, saidcircuit includng means to control the sequence of operation of saidcontact sets.

3. A relay arrangement comprising a plurality of magnetic reed contactsets each having a separate energizing coil to energize the magneticcircuit thereof including the said contact set interlinked therewith andmeans for controlling the sequence of operation of said sets comprisingan arrangement wherein the magnetic circuits of said contact sets are inseries and the energizing coils are in parallel.

4. A relay arrangement comprising a plurality of magnetic reed contactsets placed in a common energizing coil and means to control thesequence of operation of said contact sets.

5. A relay arrangement comprising a plurality of separate contact setseach having an individual energizing coil, a circuit including all ofsaid energizing coils responsive to a single circuit operation and meansto control the sequence of operation of said contact sets.

6. A relay arrangement comprising a plurality of separate contact setseach having a separate energizing coil, all said coils being included ina single circuit, two control points in said circuit, and means in saidcircuit responsve to the order of operation of said control points fordifferently controlling the sequence of operation of said contact sets.

7. A relay arrangement comprising a plurality of separate contact setseach having a separate energizing coil, all said coils being included ina single circuit and responsive to closing and opening circuitoperations at different points in said circuit for changing the sequenceof operation and release of said contact sets, and means in said circuitfor causing said contact sets to operate and release in different timeintervals.

8. A relay arrangement comprising a makebefore-break arrangementconsisting of a fixed magnetic element and two relatively movablemagnetic elements arranged in the form of a magnetic circuit having aplurality of air gaps in series, an electrical coil for energizing saidmagnetic circuit, an electrical contact closed through the closure ofone of said air gaps, the closure of said one air gap acting to lowerthe reluctance of the said magnetic circuit and accelerate the closureof another of said air gaps and another electrical contact openedthrough the closure of said other air gap.

9. A relay arrangement consisting of a plurality of separate contactsets each having an individual magnetic circuit, and means forcontrolling the simultaneous operation of said contact sets comprising asingle coil interlinked with said individual magnetic circuits.

10. A relay arrangement consisting of a coil having a plurality ofcontact sets axially disposed therein and means to control the relativetimes of the operation of said contact sets upon the energization ofsaid coil, consisting of an individual strip of magnetic materialpassing over the outside of said coil from one end of each said contactset to the other end thereof comprising an individual low reluctancepath for each said contact set.

11. In a relay device, a pluralit of magnetic reed contact units eachconstituting a link in a magnetic circuit for its operation, anelectrical circuit interlinked with the said magnetic reed contactunits, said magnetic units being combined with said electrical circuitin a mutually controlling relationship to each other whereby the changein reluctance through one said unit upon its operation will afiect andchange the normal time of operation of another said unit.

12. In a relay device, a plurality of magnetic reed contact unitsincluded in a magnetic circuit and each forming a branch thereof, eachof said contact units becoming operated upon the energization of saidmagnetic circuit, an electrical circuit for the energization of saidmagnetic circuit including all of its said branches, said branchcircuits being arranged in a mutually controlling relationship to eachother whereby the sequence of operation of said contact units may beprearranged and controlled.

JOHN T. L. BROWN.

